Cardiac visualization devices and methods

ABSTRACT

Devices and methods for facilitating transvascular, minimally invasive and other “less invasive” surgical procedures generally include a sheath with an expandable balloon at the distal end, an inflation lumen for expanding the balloon, and a device passage lumen for allowing passage of one or more surgical instruments. The sheath is configured to house at least one visualization device such that an optical element of the device is positioned to view the surgical site. In some embodiments, instruments may be passed through the sheath, with the distal balloon partially or fully circumscribing or encircling the instruments. Any suitable instrument(s) may be passed through sheaths of the invention, such as a surgical clip applier for repairing a heart valve, an ablation member for treating atrial fibrillation, one or more pacemaker leads, a coronary sinus access device or the like.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Application 60/500,733 filedon Sep. 3, 2003 (Attorney Docket (GDS 1010-1).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to medical devices and methods.More particularly, the invention relates to visualization devices andmethods for facilitating cardiac surgical procedures, such as repair ofthe mitral or tricuspid valve for treating mitral or tricuspidregurgitation.

In recent years, many advances have been made to reduce the invasivenessof cardiac surgery. In an attempt to avoid open, stopped-heartprocedures, which may be accompanied by high patient morbidity andmortality, many devices and methods have been developed for operating ona heart through smaller incisions, operating on a beating heart, andeven performing cardiac procedures via transvascular access. Differenttypes of cardiac procedures, such as cardiac ablation techniques fortreating atrial fibrillation, stenting procedures for atherosclerosis,and valve repair procedures for treating conditions such as mitralregurgitation have experienced significant technological advances. Inimplementing many, if not all, transvascular, minimally invasive andother cardiac surgery techniques, visualization of the heart, thesurgical field, surrounding structures, and the like is essential. Atthe same time, visualization is often difficult, due to the rapidmovement of a beating heart as well as the large quantities of pumpingblood in an intracardiac surgical field.

One type of cardiac surgery which may benefit from less invasivetechniques is heart valve repair. Traditional treatment of heart valvestenosis or regurgitation, such as mitral or tricuspid regurgitation,typically involves an open-heart surgical procedure to replace or repairthe valve. Valve repair procedures typically involve annuloplasty, a setof techniques designed to restore the valve annulus shape and strengthenthe annulus. Conventional annuloplasty surgery generally requires alarge incision into the thorax of the patient (a thoracotomy), andsometimes a median sternotomy (cutting through the middle of thesternum). These open heart, open chest procedures routinely involveplacing the patient on a cardiopulmonary bypass machine for sustainedperiods so that the patient's heart and lungs can be artificiallystopped during the procedure. Finally, valve repair and replacementprocedures are typically technically challenging and require arelatively large incision through the wall of the heart to access thevalve.

Due to the highly invasive nature of open heart valve repair orreplacement, many patients, such as elderly patients, patients havingrecently undergone other surgical procedures, patients with comorbidmedical conditions, children, late-stage heart failure patients, and thelike, are often considered too high-risk to undergo heart valve surgeryand are relegated to progressive deterioration and cardiac enlargement.Often, such patients have no feasible alternative treatments for theirheart valve conditions.

To obviate this situation, a number of devices and methods for repairinga mitral valve to treat mitral regurgitation in a less invasive mannerhave been developed. Some devices provide for heart valve repair throughminimally invasive incisions or intravascularly, while others improveupon open heart surgical procedures on beating hearts, stopped hearts orboth. For example, several improved devices and methods for heart valverepair are described in one or more patent applications filed by theinventors of the present invention and assigned to the assignee of thepresent invention. For further description of such devices and methods,reference may be made to U.S. patent application Ser. No. 10/461043(Attorney Docket No. 16886-000310), filed on Jun. 13, 2003, which ishereby incorporated fully by reference.

As mentioned above, one of the main challenges in performing minimallyinvasive surgery on a heart, heart valve, or any other structure isobtaining adequate visualization of the structure and the surgicalfield. Visualizing a cardiac valve annulus in a beating heart procedureis especially challenging due to rapid movement of the annulus and theheart, the small size of the annulus, and the blood-filled surgicalfield. Current visualization of minimally invasive cardiac procedures istypically accomplished via transesophageal echocardiogram (TEE).Although this technique works relatively well for some cardiacprocedures, it does not provide as clear a picture of the surgical siteas would direct visualization. Thus, TEE may not be sufficient forvisualizing a minimally invasive procedure within the heart, especiallya beating heart procedure to repair a valve annulus.

To obtain direct visualization within the heart, any suitable endoscopicdevice may be introduced into the heart, such as a conventionalendoscope or ultrasonic probe. One problem encountered with suchdevices, however, is that their ability to provide visualization isoften severely reduced by the presence of blood in the heart thatsurrounds the optic element of the visualization device. A number ofdevices have been described to combat this problem. For example, U.S.Pat. No. 6,346,074, issued to Roth on Feb. 12, 2002, describes anendoscope having a distal balloon over its end. Such devices still havecertain shortcomings, however. For example, balloon-covered endoscopedevices are typically introduced into the surgical site through a sheathor introducer device separately from any of the instruments used toperform the cardiac procedure. Thus, the visualization device musttypically be manipulated apart from the surgical instruments, and theoptical element of the device may often be positioned significantlyapart from the working ends of the instruments and the surgical site. Inother balloon endoscope devices, the endoscope must be advanced to thesurgical site to visualize the site and then removed to allow a surgicalinstrument to be advanced through the same sheath to perform theprocedure. Obviously, such a technique may require numerous, awkwardswitch-outs of endoscope and surgical instrument and will not result indirect, real-time visualization of the procedure.

Many minimally invasive or “less invasive” surgical procedures otherthan heart valve repair would also benefit from improved visualization.For example, improved visualization could facilitate other cardiacprocedures, such as accessing the coronary sinus for placement of animplantable device or for performing a procedure, placing pacemakerleads in one or more areas of the heart, ablation procedures such asablation around the pulmonary veins to treat atrial fibrillation,atrial-septal defect repair procedures, and the like. Improvedvisualization could also be used to enhance non-cardiac procedures suchcinching or otherwise treating a bladder, stomach, gastroesophagealjunction, vascular structure, gall bladder or the like.

Therefore, it would be beneficial to have improved visualization devicesand methods for use in transvascular, minimally invasive and other “lessinvasive” surgical procedures, such as heart valve repair and othercardiac procedures. Devices and methods for providing such visualizationwould ideally be minimally invasive and would enhance a physician'sability to locate, visualize and repair a valve annulus, atrial-septaldefect, or other cardiac structure accurately and efficiently. Ideally,visualization of the surgical site would be as direct as possible, withan optic element of the visualization device being positioned close tothe site. Also ideally, the visualization device would providevisualization at the same time that the physician was performing theprocedure and further provide or facilitate access for surgical and/ordiagnostic instruments to operate in the visualized field. At least someof these objectives will be met by the present invention.

2. Description of the Background Art

U.S. Pat. No. 6,346,074 describes an endoscope having a balloon over itsdistal end for use in intracardiac surgery. Patent publications relatedto mitral valve repair include WO01/26586; US2002/0163784A12;US2002/0156526; US2002/0042621; 2002/0087169; US2001/0005787;US2001/0014800; US2002/0013621; US2002/0029080; US2002/0035361;US2002/0042621; US2002/0095167; and US2003/0074012. U.S. patents relatedto mitral valve repair include U.S. Pat. Nos. 4,014,492; 4,042,979;4,043,504; 4,055,861; 4,700,250; 5,366,479; 5,450,860; 5,571,215;5,674,279; 5,709,695; 5,752,518; 5,848,969; 5,860,992; 5,904,651;5,961,539; 5,972,004; 6,165,183; 6,197,017; 6,250,308; 6,260,552;6,283,993; 6,269,819; 6,312,447; 6,332,893; and 6,524,338. Publicationsof interest include De Simone et al. (1993) Am. J. Cardiol. 73:721-722and Downing et al. (2001) Heart Surgery Forum, Abstract 7025.

BRIEF SUMMARY OF THE INVENTION

Devices and methods of the present invention facilitate transvascular,minimally invasive and other “less invasive” surgical procedures, suchas heart valve repair procedures, by providing direct visualization of asurgical site. “Less invasive,” for the purposes of this application,means any procedure that is less invasive than traditional,large-incision open surgical procedures. Thus, a less invasive proceduremay be an open surgical procedure involving one or more smallerincisions, a transvascular percutaneous procedure, a transvascularprocedure via out-down, a laparoscopic procedure, or the like.Generally, any procedure in which a goal is to minimize or reduceinvasiveness to the patient may be considered less invasive.Furthermore, although the terms “less invasive” and “minimally invasive”may sometimes be used interchangeably in this application, neither thesenor other descriptive terms should be interpreted to limit the scope ofthe invention. Generally, visualization devices and methods of theinvention may be used in performing or enhancing any suitable procedure.

In addition to facilitating visualization, devices and methods of theinvention also facilitate access for positioning one or more instrumentsto the surgical site for performing a procedure. The devices generallyinclude a sheath with an expandable balloon at the distal end, aninflation lumen for expanding the balloon, and a device passage lumenfor allowing passage of one or more surgical instruments. The sheath isconfigured to house at least one visualization device such that anoptical element of the device is positioned to view the surgical site.In some embodiments, instruments may be passed through the sheath, withthe distal balloon partially or fully circumscribing or encircling theinstruments. In other embodiments, the balloon may be adjacent, but notencircling, a lumen for instrument passage. Any suitable instrument(s)may be passed through sheaths of the invention, such as a surgical clipapplier for repairing a heart valve, an ablation member for treatingatrial fibrillation, a suturing device, and/or the like. By positioninga lumen for passage of instruments adjacent a balloon-coveredvisualization device, sheaths of the present invention provide improved,direct visualization of a surgical site for performing a procedure.

As mentioned above, the present application often focuses onvisualization devices and methods as used in heart valve repair, andmore specifically mitral valve repair to treat mitral regurgitation. Itshould be emphasized, however, that visualization devices and methods ofthe invention may be used in any suitable procedure, both cardiac andnon-cardiac. For example, they may be used in procedures to repair theaortic or pulmonary valve, to repair an atrial-septal defect, to accessand possibly perform a procedure from the coronary sinus, to place oneor more pacemaker leads, to perform a cardiac ablation procedure, and/orthe like. In other embodiments, the devices and methods may be used toenhance a laparoscopic or other endoscopic procedure on any part of thebody, such as the bladder, stomach, gastroesophageal junction,vasculature, gall bladder, or the like. Therefore, although thefollowing description typically focuses on mitral valve and other heartvalve repair, such description should not be interpreted to limit thescope of the invention as defined by the claims.

That being said, in one aspect of the invention, a method for performinga procedure on a heart involves first advancing an elongate sheath to alocation in the heart for performing the procedure. Next, an expandableballoon coupled with a distal end of the elongate sheath is inflated andthe location in the heart is visualized through the expandable balloon,using at least one visualization device disposed in the elongate sheath.Finally, at least part of the procedure is performed using one or moreinstruments extending through a first lumen of the elongate sheath.

In some embodiments, the elongate sheath may be flexible so that it maybe advanced through the vasculature of a patient to position at least adistal portion of the sheath in the heart. For example, the sheath maybe advanced through the internal jugular vein, superior vena cava, rightatrium and interatrial septum of the patient to position the distalportion of the sheath in the left atrium. Alternatively, the sheath maybe advanced through the internal jugular vein, superior vena cava, rightatrium, coronary sinus and left atrial wall of the patient to positionthe distal portion of the sheath in the left atrium. In still anotherembodiment, a flexible sheath may be advanced through the femoral vein,inferior vena cava, right atrium and interatrial septum. In otherembodiments, the sheath may be rigid and may be introduced viathorascopically or otherwise through the heart wall.

Inflating the balloon typically involves injecting a fluid into theballoon via a second lumen in the sheath, though any other inflationmethod may be used. The balloon may have any shape, such as a toroidalballoon encircling the first lumen or a spherical or ovoid balloonadjacent the first lumen. Optionally, methods may further includepassing at least one fluid through the first lumen to flush the locationfor performing the procedure and/or to cleanse one or more instrumentspositioned in the first lumen. Also optionally, a method may includeretracting an outer tubular member to expose additional expandableballoon material from the distal end of the sheath and further inflatingthe expandable balloon.

The visualizing step may be performed using any suitable visualizationdevice in any location. For example, a fiberoptic viewing scope,typically in combination with a fiberoptic or other illuminator may beused. Another embodiment may employ a charge coupled device withillumination, essentially a small camera, for visualization. In someembodiments, the visualization device is disposed within the elongatesheath for visualizing the surgical site. Sometimes, the visualizationdevice is disposed in a second lumen of the sheath, the second lumencomprising an inflation lumen for inflating the expandable balloon. Insome embodiments, a separate visualization device may be passed into thesheath through the second lumen to position the visualization device forvisualizing the location. In some embodiments, the visualization deviceis disposed between an outer tubular member and an inner tubular memberof the sheath. The annular space between the two tubular members mayalso act as an inflation lumen.

Optionally, the method may include visualizing a first view of thelocation with the visualization device in a first position in thesheath, moving the visualization device to at least a second position inthe sheath, and visualizing a second view of the location with thevisualization device in the second position. Thus, two or more differentviews of a surgical site may be acquired using the sheath device and onevisualization device; Alternatively, visualization of multiple views maybe accomplished via a plurality of visualization devices disposed atvarious positions in the sheath, for example, disposed at differentcircumferential positions surrounding a central device passage lumen. Inthese and other embodiments, a central processing unit may be used toprocess captured images of the surgical site. Such processed images maythen be transmitted proximally for viewing by the physician. Forexample, in one embodiment visualization may be achieved using a lightsource and one or more sensors or detectors disposed in a 360-degreearray around an inner, device-passage lumen, the light source and thedetectors disposed at the distal end of a visualization device. Thesensors may then be coupled with a charge coupled device (CCD) disposednear the distal end of the device, the CCD being coupled with a wirethat transmits data proximally along the visualization device.

Any suitable surgical procedure may be performed using the devices andmethods of the invention. Typically, the procedures will betransvascular, minimally invasive, or other “less invasive” procedures,as discussed above. In some embodiments, the procedure involvesrepairing a heart valve, such as a mitral, tricuspid, aortic orpulmonary valve. For example, repairing the valve may involve applyingclips to a valve annulus using a clip applier extending through thefirst lumen of the sheath. Such a procedure may further include cinchinga tether coupled with the applied clips to decrease a diameter of thevalve annulus. In some embodiments, the procedure may be furtherenhanced by passing a fluid, such as saline, through the first lumen ina direction from a proximal end of the sheath toward the distal end ofthe sheath to cleanse the surgical instrument(s), clear an area aroundthe surgical site, and/or cleanse the external surface of the balloon.

In another aspect, a device for facilitating a procedure on a heartincludes an elongate sheath having a proximal end, a distal end, a firstlumen extending from the proximal end to the distal end, and at least asecond lumen, and an expandable balloon coupled with the elongate sheathat or near the distal end, wherein the balloon at least partiallyencircles the first lumen, and the second lumen opens into the balloonfor inflating the balloon. The elongate sheath may include one or morerigid tubular members and/or one or more flexible tubular members. Insome embodiments, for example, the sheath includes an inner tubularmember having an inner surface defining the first lumen and an outertubular member disposed over the inner tubular member. In suchembodiments, the annular space between the inner tubular member and theouter tubular member may form the second lumen.

The expandable balloon may be coupled with the inner tubular member andthe outer tubular member at or near the distal end of the sheath suchthat the second lumen acts as an inflation lumen. Such a balloon may betoroidal in shape, for example, with the first lumen being continuouswith a central aperture in the toroidal balloon. Optionally, the outermember may be slidable proximally to expose additional material of theexpandable balloon to allow the balloon to further expand. In analternative embodiment, an slidable outer sleeve may be disposed overthe outer tubular member to provide for additional exposure andexpansion of an expandable balloon.

The sheath may also include at least one visualization device disposedwithin the second lumen. For example, the visualization device mayinclude one or more fiber optic devices, ultrasound transducers, chargecoupled devices, cameras, light sources and/or sensors. In someembodiments, the distal end of the visualization device is disposedwithin the expandable balloon. Also in some embodiments, thevisualization device is movable within the sheath. For example, wherethe sheath comprises an inner tubular member and an outer tubular memberand the second lumen comprises an annular space between the inner andouter tubular members, the visualization member may be movable aroundthe circumference of the second lumen. In alternative embodiments, thesheath may not include a visualization device but may have a lumen, suchas the second lumen, that is sufficiently large to allow passage of atleast one visualization device to position a distal end of the devicewithin the expandable balloon.

In some embodiments, the inner diameter of the first lumen issufficiently large to allow passage of at least one instrument forperforming the procedure on the heart. A variety of surgical instrumentsmay thus be passed, though they will often be catheter-based,transvascular, or other less invasive instruments. In one embodiment,the instrument is clip applier for applying a plurality of tetheredclips to a valve annulus of the heart and cinching a tether coupled withthe clips to reduce a diameter of the valve. In another embodiment, theinstrument may be an ablation member for ablating a portion of theheart, such as in a procedure to treat atrial fibrillation.

In another aspect of the invention, a device for facilitating aprocedure on a heart includes an elongate sheath having a proximal end,a distal end, a first lumen extending from the proximal end to thedistal end, and at least a second lumen, and an expandable ballooncoupled with the elongate sheath at or near the distal end and adjacentthe first lumen, wherein the second lumen opens into the balloon forinflating the balloon. Unlike the embodiment just described, here thesurgical instrument(s) may pass adjacent to but not through the balloon.Typically, in such embodiments, the balloon will have a spherical, ovoidor other suitable shape, but will not be toroidal or “donut-shaped” asin the embodiments described above. These and other embodiments aredescribed more fully below, with reference to the appended drawingfigures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a frontal, cross-sectional view of a human heart with avisualization device positioned for performing an intracardiacprocedure, in accordance with one embodiment of the present invention;

FIG. 2 is a perspective view of a visualization device for performing aminimally invasive cardiac procedure, in accordance with one embodimentof the present invention;

FIG. 3 is a side, cross-sectional view of the visualization device inFIG. 2; and

FIG. 4 is a perspective view of a visualization device for performing aminimally invasive cardiac procedure, in accordance with anotherembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Devices and methods for facilitating transvascular, minimally invasiveand other “less invasive” surgical procedures generally include a sheathwith an expandable balloon at the distal end, an inflation lumen forexpanding the balloon, and a device passage lumen for allowing passageof one or more surgical instruments. The sheath is configured to houseat least one visualization device such that an optical element of thedevice is positioned to view the surgical site. In some embodiments,instruments may be passed through the sheath, with the distal balloonpartially or fully circumscribing or encircling the instruments. Inother embodiments, the balloon may be adjacent, but not encircling, alumen for instrument passage. Any suitable instrument(s) may be passedthrough sheaths of the invention, such as a surgical clip applier forrepairing a heart valve, an ablation member for treating atrialfibrillation, a suturing device, and/or the like. By positioning a lumenfor passage of instruments adjacent a balloon-covered visualizationdevice, sheaths of the present invention provide improved, directvisualization of a surgical site for performing a procedure.

As discussed above, the present application often focuses onvisualization devices and methods as used in heart valve repair, andmore specifically mitral valve repair to treat mitral regurgitation. Itshould be emphasized, however, that visualization devices and methods ofthe invention may be used in any suitable procedure, both cardiac andnon-cardiac. For example, they may be used in procedures to repair theaortic or pulmonary valve, to repair an atrial-septal defect, to accessand possibly perform a procedure from the coronary sinus, to place oneor more pacemaker leads, to perform a cardiac ablation procedure, and/orthe like. In other embodiments, the devices and methods may be used toenhance a laparoscopic or other endoscopic procedure on any part of thebody, such as the bladder, stomach, gastroesophageal junction,vasculature, gall bladder, or the like. Therefore, although thefollowing description typically focuses on mitral valve and other heartvalve repair, such description should not be interpreted to limit thescope of the invention as defined by the claims.

That being said, and referring now to FIG. 1, an exemplary sheath 10 ofthe present invention suitably comprises an elongate tubular member 11having a distal end and a proximal end. An expandable balloon 12 istypically coupled with sheath 10 at or near the distal end, and one ormore treatment devices 14 may be passed through an aperture in thedistal end. One or more visualization devices (not shown) may be coupledwith or inserted into sheath 10 such that an optical element of thevisualization device(s) extends up to or within balloon 12.

Generally, sheath 10 may be flexible, rigid, or part-flexiblepart-rigid, and may be introduced to a surgical site via any suitablemethod or route. In FIG. 1, for example, sheath 10 has been advanced tothe mitral valve MV of a heart H through the superior vena cava SVC,right atrium RA, foramen ovale FO, and left atrium LA. Access to thesuperior vena cava SVC may be gained, for example, via the internaljugular vein. In other embodiments, access to the RA may be gainedthrough the femoral vein and the inferior vena cava. Thus, access to theheart H may be achieved via a transvascular route. Alternatively, sheath10 may be introduced through an incision and/or access port in the wallof the left atrium LA. Such access is discussed more fully in U.S.patent application Ser. No. 10/461043 (Attorney Docket No.16886-000310), previously incorporated by reference. Any other suitableminimally invasive means for gaining access may alternatively be used toposition sheath 10 in a desired location for visualizing and performinga procedure.

Referring now to FIGS. 2 and 3, one embodiment of sheath 10 suitablyincludes an outer tubular member 11 and an inner tubular member 13, withthe annular space between the two tubular members comprising aninflation lumen 22 and the space within inner tubular member 13comprising a device passage lumen 20. An expandable balloon 12 iscoupled with at least one of the two tubular members at or near thedistal end of sheath 10. In FIGS. 2 and 3, balloon 12 is coupled withboth tubular members such that inflation lumen 22 opens distally intoballoon 12. In this embodiment, balloon 12 has a toroidal or “donut”shape, such that balloon 12 encircles device passage lumen 20, and anaperture 15 in balloon 12 allows one or more treatment devices 14 toextend from the distal end of device passage lumen 20 through balloon12. A visualization device 24 is disposed within inflation lumen 22 suchthat a distal portion of visualization device 24, including an opticalelement 26, extends into balloon 12. Treatment device 14 in thisembodiment comprises a clip applier for applying tethered clips to aheart valve annulus, shown with a protruding clip 16 and clip tether 18.Clip appliers for heart valve repair are described more fully in U.S.patent application Ser. No. 10/461043, previously incorporated byreference. Of course, any other suitable treatment device mayalternatively be used with sheath 10, such as a hook applier, a sutureapplier, an ablation device, a scalpel or other cutting device such asan electrocautery device, and/or the like.

Inner tubular member 13 and outer tubular member 11 of sheath 10 maycomprise any suitable material or combination of materials and may haveany suitable shape, size, diameters, thicknesses and the like. Invarious embodiments, tubular members 1 1, 13 may be flexible along theirentire lengths, rigid along their entire lengths or part-flexible,part-rigid. The members 11, 13 may be composed of one or more metals,such as Nitinol, stainless steel or titanium; flexible or rigidpolymers, such as polyurethane, polytetrafluoroethylene (PTFE), otherfluoropolymers, PEAX®, and/or the like; or any other suitable materialor combination of materials. In some embodiments, tubular members 11, 13may be rigidly fixed to one another, while in other embodiments one ofthe members 11, 13 may be movable relative to the other. For example, inone embodiment outer tubular member 11 is slidably disposed over innertubular member 13 so that it can retract proximally over inner tubularmember 13 and then extend back distally to its original position.

As shown in FIG. 3, a slidable outer tubular member 11 may allow thesize of balloon 12 to be adjusted by a user. Balloon 12 may be coupledwith outer tubular-member 11 at an attachment point 30 such that slidingouter tubular member 11 proximally and introducing additional fluid orother inflating substance into balloon 12 will cause balloon 12 tofurther expand. Any suitable configuration of balloon material andattachment point 30 may be used. In one embodiment, for example, balloonmaterial may be housed in a small slit or housing coupled with outertubular member 11.

In an alternative embodiment, outer tubular member 11 may be fixed,rather than slidable, and an outer, slidable sleeve (not shown) may bedisposed over outer tubular member 11. The outer, slidable sleeve may bemoved distally to contain part of balloon 12 and moved proximally torelease part of balloon 12 to allow for additional expansion. Allowing auser to adjust the size of balloon 12 by sliding outer tubular member 11proximally or distally and possibly by introducing additional inflationfluid may improve the users ability to visualize the surgical site.Balloon expansion, for example, may help exclude additional blood and/orpush aside surrounding tissue from the surgical site.

It may sometimes be advantageous to introduce a fluid substance intodevice passage lumen 20 to cleanse devices, cleanse balloon 12, clear anarea around the surgical site and/or the like. In one embodiment, forexample, saline may be introduced proximally with sufficient force topropel it forward (distally) through device passage lumen 20 to “flush”lumen 20. Introduction of saline or other fluids may be accomplished viaany suitable proximal inlet, such as a valve on a Y-connector device orthe like.

Balloon 12 may have any suitable size, shape and configuration and maybe made from any suitable expandable material. Although a toroidalballoon is shown in FIGS. 2 and 3, alternative embodiments may include aspherical, ovoid or otherwise shaped balloon disposed adjacent a lumenfor instrument passage but not encircling the lumen. Such an embodimentis described further below with reference to FIG. 4. Similarly, anysuitable inflation lumen may be included in sheath 10 for expandingballoon 12. In some embodiments, inflation lumen 22 is formed by theannular space between outer tubular member 11 and inner tubular member13. Thus, inflation lumen 22 may comprise a circumferential lumen.Alternatively, one or more tubular lumens may be disposed within theannular space between outer tubular member 11 and inner tubular member13. Any means for inflating balloon 12 is contemplated within the scopeof the invention. Typically, balloon 12 is inflated by introducing afluid, such as saline, into balloon 12 via inflation lumen 22, althoughany other inflation technique or substance may be used.

Similarly, device passage lumen 20 may have any suitable size, diameterand the like and may be disposed in any location through sheath 10.Thus, device passage lumen 20 may open into aperture 15 through balloon12, or may alternatively open adjacent (but not through) balloon 12.Lumen 20 may allow passage of any suitable device or devices, such as asurgical clip applier 14 for applying clips 16, coupled with a tether18, to a heart valve annulus. In other embodiments, ablation devices,electrocautery devices, suturing devices, cutting devices, and/or thelike may be passed through device passage lumen 20. Again, any and allsuitable devices are contemplated.

Sheath 10 may also include one or more visualization devices 24. In someembodiments, visualization device 24 is included as part of sheath 10,while in other embodiments, a separate visualization device 24 may beinserted into sheath 10 by a user. These latter embodiments may allow,for example, a physician to use an already-owned visualization device orother device with sheath 10. Visualization device 24 itself may compriseany suitable device, such as a fiber optic device, an ultrasonic device,a charge coupled device, a camera, or the like. In embodiments wherevisualization device 24 is included, it may be coupled with sheath 10 inany suitable manner. For example, visualization device 24 may bedisposed within inflation lumen 22 in such a way that it can move withinlumen 22. In an embodiment as shown in FIGS. 2 and 3, visualizationdevice 24 may be movable around the circumference of inflation lumen 22,thus encircling device passage lumen 20. Such movement allows a user toacquire views of the surgical site from multiple angles.

In some embodiments, multiple visualization devices 24 or avisualization device disposed around a length of the distal end ofsheath 10 may be used to visualize the site from multiple angles. Tofurther enhance visualization, some embodiments may include a centralprocessing unit (CPU) at or near the distal end of sheath 10 forprocessing images captured by visualization device 24. Processed imagescould then be transmitted proximally along sheath 10 to provide imagesto the user. For example, in one embodiment visualization may beachieved using a light source and one or more sensors or detectorsdisposed in a 360-degree array around an inner, device-passage lumen,the light source and the detectors disposed at the distal end of avisualization device. The sensors may then be coupled with a chargecoupled device (CCD) disposed near the distal end of the device, the CCDbeing coupled with a wire that transmits data proximally along thevisualization device.

Although visualization device 24 is shown with a distal portion andoptical element 26 extending into balloon 12, in other embodimentsoptical element may be flush with, or recessed into, the distal end ofinner tubular member 13 and/or outer tubular member 11. Thus, there isno requirement that any visualization member extend into balloon 12.Such a configuration may be advantageous, in that optical element 26 maybe positioned closer to clip applier 14 or other devices and closer tothe surgical site. If an angled optical element is used, it may befurther advantageous to have the optical element facing centrallytowards the surgical instrument(s) (or in another direction towards theinstrument(s) in other embodiments).

Referring now to FIG. 4, an alternative embodiment of a sheath 40includes an outer tubular member 42, an inflation lumen 44, a balloon46, a visualization device 48, and a device passage lumen 50 forallowing passage of one or more surgical instruments 52. In contrast tothe earlier described embodiment, inflation lumen 44 does not encircledevice passage lumen 50, but instead the two lumens are adjacent oneanother. The two lumens may be placed at any suitable location throughsheath 40 and may exit sheath 40 at any suitable locations, thoughpreferably visualization device 48 will be relative close to devicepassage lumen 50 to allow for direct visualization of any surgicalinstruments passed through the lumen 50. In an alternative embodiment,multiple inflation lumens 44, multiple balloons 46 and/or multiplevisualization devices 48 may be included. As with the previouslydescribed embodiments, some sheaths will include one or morevisualization devices 48 while others will simply allow for insertion ofa user's visualization device.

Methods of the present invention generally involve first advancingsheath 10, 40 to a location in the heart for performing a minimallyinvasive heart procedure, such as a mitral or tricuspid valve repair.Next, expandable balloon 12, 46 is inflated and visualization device 24,48 is used to visualize an area within the heart, locate an area forperforming the surgical procedure, etc. The minimally invasive proceduremay then be performed, using one or more instruments 14, 52 extendingthrough device passage lumen 20, 50. During the procedure, real-timevisualization may be acquired via visualization device 24, 48. Evenbefore the procedure, visualization device 24, 48 may be used to assessthe surgical site, locate a particular structure such as a mitral valveannulus, and reposition sheath 10, 40 for better access to the site. Inmany embodiments, visualization device 24, 48 may be moved within sheath10, 40 and/or multiple visualization devices may be used to acquireimages from different perspectives and angles. Multiple surgicalinstruments may be inserted and removed through sheath, variousvisualization devices may be inserted and removed, adjustments to thesize of balloon 12, 46 may be made, and/or the like. In someembodiments, the physician may also flush one or more portions of sheathwith a fluid passed through one of the sheath's lumens. Any othersuitable method steps may be added, steps may be skipped or combined,and or alternative steps may be substituted without departing from thescope of the invention.

Although various embodiments of the present invention have beendescribed fully above, this description is for exemplary purposes onlyand should not be interpreted to limit the scope of the invention. Forexample, various alterations, additions, substitutions or the like maybe made to embodiments described above without departing from the scopeof the invention. Therefore, none of the foregoing description should beread to limit the scope of the invention as it is defined in thefollowing claims.

Any and all patents, applications and printed publications mentionedabove are hereby incorporated by reference.

1-87. (canceled)
 88. A device comprising: an elongate member having a lumen extending therethrough; and an expandable member connected to, and expandable from, the distal end of the elongate member, wherein the expandable member defines a continuous aperture along and through the entire longitudinal length of the expandable member when the expandable member is in the expanded configuration, the aperture having a diameter allowing for passage of at least one device for performing a heart procedure therethrough, wherein the device is selected from the group consisting of an ablation device, an electrocautery device, a suturing device, and a cutting device.
 89. The device of claim 88, wherein the expandable member is frustoconical.
 90. The device of claim 88, wherein the expandable member is toroidal.
 91. The device of claim 88, wherein the expandable member is an inflatable balloon.
 92. The device of claim 91, wherein the inflatable balloon comprises one or more inflation lumens.
 93. The device of claim 88, wherein a diameter of the lumen is the same as the diameter of the aperture.
 94. The device of claim 88, further comprising one or more visualization devices.
 95. The device of claim 94, wherein the visualization device is selected from the group consisting of a fiber optic device, an ultrasonic device, a charge coupled device, and a camera.
 96. The device of claim 88, wherein the elongate member is slidably disposed within an outer tubular member.
 97. The device of claim 96, wherein the length of the expandable member is adjusted by sliding the outer tubular member along the elongate member.
 98. The device of claim 88, wherein the elongate member is flexible.
 99. The device of claim 88, wherein the elongate member is a catheter.
 100. A method comprising: advancing an elongate member having a lumen extending therethrough adjacent to heart tissue; expanding an expandable member connected to, and expandable from, a distal end of an elongate member, wherein the expandable member defines a continuous aperture along and through the entire longitudinal length thereof; and advancing at least one device through the continuous aperture where the device is selected from the group consisting of an ablation device, an electrocautery device, a suturing device, and a cutting device.
 101. The method of claim 99, further comprising adjusting the size of the expandable member by sliding a sheath along the elongate member.
 102. The method of claim 99, further comprising visualizing the location using a visualization device disposed within the expandable member.
 103. The method of claim 99, wherein the heart procedure is mitral valve repair.
 104. The method of claim 99, wherein the heart procedure is a laparoscopic procedure.
 105. The method of claim 99, wherein the elongate member is advanced through the superior vena cava into the right atrium and through the interatrial septum.
 106. The method of claim 99, wherein the elongate member is advanced through the inferior vena cava into the right atrium and through the interatrial septum.
 107. A device comprising: an elongate member having a lumen extending therethrough; and an expandable member having a proximal end directly coupled to, and expandable from, the distal end of the elongate member, wherein the expandable member defines a continuous aperture along and through the entire longitudinal length of the expandable member when the expandable member is in the expanded configuration, the aperture having a diameter allowing for passage of at least one device for performing a heart procedure therethrough, wherein the device is selected from the group consisting of an ablation device, an electrocautery device, a suturing device, and a cutting device.
 108. The device of claim 107, further comprising a visualization device disposed within the expandable member. 